五羟黄酮调节肝癌HepG2细胞bax基因表达诱导细胞凋亡的实验研究

Quercetin regulates bax gene expression and induces apoptosis in hepatocellular carcinoma HepG2 cells

目的探讨三磷酸肌醇(IP3)和bax基因表达变化在五羟黄酮(Quercetin)诱导肝癌细胞凋亡中的作用。方法以肝癌HepG2细胞培养72h为对照,以20,40,60,80μmol/L Quercetin作用于HepG2细胞72h时和60μmol/LQuercetin作用于HepG2细胞6,12,24,48,72h,应用同位素试剂盒检测细胞IP3含量,RT-PCR分析bax mRNA表达,Western blotting分析细胞bax蛋白表达,流式细胞仪检测细胞凋亡率。结果各浓度的Quercetin作用于肝癌HepG2细胞72h,IP3含量显著低于对照组(P<0.01),bax mRNA和bax蛋白表达显著高于对照组,细胞凋亡率显著高于对照组(P<0.01);60μmol/L Quercetin作用于肝癌HepG2细胞6,12,24,48,72h,各时相IP3含量显著低于对照组(P<0.01);12h后bax mRNA和bax蛋白表达显著高于对照组,24h后各时相细胞凋亡率为显著高于对照组(P<0.01)。结论Quercetin能减少IP3生成,上调bax基因表达,诱导肝癌细胞凋亡。

Objective To explore the role of 1 , 4, 5-trisphosphate inositol （ IP3 ） and bax gene expression in apoptosis of HepG2 cells induced by Quercetin. Methods HepG2 cells were cultured for 72h as control. HepG2 ceils were treated with different concentrations including 20,40.60,80/μmol/L Quercetin for 72h, and treated with 60/μmol/ L Quercetin for 12h, 24h, 48h and 72h. IP3 , bax mRNA, bax protein and apoptosis rate were assayed by IP3-[↑3 H ] Birtrak assay, RT-PCR, Western blotting and flow cytometry, respectively. Results In HepG2 cells incubated with each of the concentrations of Quercetin for 72 h, IP3 continent was lower than that of control （ P 〈 0.01 ） , bax mRNA expression and bax protein expression was higher than that of control, and the apoptosis rate was higher than that of control; in HepG2 cells incubated with Quercetin for 6 h, 12 h, 24 h, 48 h, 72 h, IP3content was lower than that of control （P〈0.01） ;bax mRNA and bax protein expression in groups incubated with 60 μmol/L Quercetin for 12h was higher than that of control, and the apoptosis rate in groups incubated with 60μmol/ L Quercetin for 24h, 48h and 72h was significantly higher than that in control （ P〈0.01 ）. Conclusions Quercetin induces apoptosis of HepG2 ceils by reducing IP3 production and up-regulating bax gene expression.